<template>
  <div id="app">
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody v-if="list.length">
          <tr v-for="(obj, index) in list" :key="obj.id">
            <td>{{ obj.id }}</td>
            <td>{{ obj.name }}</td>

            <!-- 如果价格超过100，就有red这个类 -->
            <td :class="obj.price >= 100 ? 'red' : ''">{{ obj.price }}</td>
            <td>{{ obj.time | formatTime }}</td>
            <td><a href="#" @click="del(index)">删除</a></td>
          </tr>
          <tr>
            <td>统计:</td>
            <td colspan="2">总价:{{ total }}</td>
            <td colspan="2">均价:{{ avgPrice }}</td>
          </tr>
        </tbody>

        <tfoot v-else>
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>

      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="资产名称"
              v-model="name"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="价格"
              v-model.number="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary" @click.prevent="add">添加资产</button>
      </form>
    </div>
  </div>
</template>

<script>
import moment from "moment";

export default {
  watch: {
    list: {
      deep: true,
      handler(newVal){
         localStorage.setItem("list",JSON.stringify(newVal))
      },
    },
  },
  data() {
    return {
      name: "",
      price: "",
      // 资产列表数组
      list: JSON.parse(localStorage.getItem("list"))  ||[
        { id: 100, name: "外套", price: 199, time: new Date("2010-08-12") },
        { id: 101, name: "裤子", price: 34, time: new Date("2013-09-01") },
        { id: 102, name: "鞋", price: 25.4, time: new Date("2018-11-22") },
        { id: 103, name: "头发", price: 19900, time: new Date("2020-12-12") },
      ],
    };
  },
  methods: {
    add() {
      if (!this.name || !this.price) {
        alert("名称或价格不能为空");
        return;
      }
      let id = this.list.length ? this.list[this.list.length - 1].id + 1 : 10;
      const obj = {
        id,
        name: this.name,
        price: this.price,
        time: new Date(),
      };
      this.list.push(obj);
      this.name = this.price = "";
    },
    del(i) {
      this.list.splice(i, 1);
    },
  },
  computed: {
    total() {
      return this.list.reduce((accu, val) => {
        return accu + val.price;
      }, 0);
    },
    avgPrice() {
      return this.total / this.list.length;
    },
  },
  filters: {
    formatTime(data) {
      return moment(data).format("YYYY-MM-DD");
    },
  },
};
</script>

<style >
.red {
  color: red;
}
</style>